焦化废水中不同极性组分的光谱分析及可生物降解特性

焦化废水是典型难降解工业有机废水,构成其成分的复杂及种类的繁多使其难以实现高效的生物降解过程,制约了水处理的水质达标.为了探明其中生物降解强抑制组分,采用DAX-8大孔树脂将焦化废水分离出疏水酸性组分(HOA)、疏水碱性组分(HOB)、疏水中性组分(HON)和亲水性组分(HIS)等4种极性不同的组分,分析了各组分的有机物含量分布,紫外吸收光谱和三维荧光光谱,并用两种方法考察了各组分的可生物降解性能.结果表明,HOA是主要的有机组分,其COD和TOC分别占比55.9%和56.8%;HOA也是主要的芳香物质及荧光组分,而HON是芳香构造化程度最高和类腐殖质占比P(Ⅲ+Ⅴ)最高的组分;各组分的BOD5/COD值及脱氢酶活性的抑制结果显示其难降解程度依次为HONHOBHIS原水HOA,而HON是焦化废水中生物抑制最强组分,其BOD5/COD值仅为0.21±0.02,对脱氢酶活性的抑制达到38.5%;SUVA和P(Ⅲ+Ⅴ)与可生物降解性的关联分析发现,焦化废水中难降解组分并不都是芳香性化合物造成的,类腐殖质对其中难降解有机组分的指示作用相比SUVA更加灵敏.     

Comparisons and critical assessment of global and diffuse solar irradiation estimation methodologies

Defining better methodologies of accurate predictions of the amount of monthly mean daily global and diffuse solar irradiation exposed is of utmost importance in order to determine the potential for utilizing the solar energy. This study compares and discusses the main methodologies, databases, and software that are used in estimating the solar irradiation to be used for the short- and long-term performances and feasibilities of solar energy systems, especially photovoltaic power plants in Turkey, and addresses the best one to be used to make the most accurate estimations. The comparisons are carried out between the recent methodologies developed by the authors, some models taken from the related literature that are concluded to be better, a widely used database, namely Meteonorm, and a widely used software, namely EU PVGIS. The reference data to develop the methodologies and to make comparison are provided from the State Meteorological Service of Turkey, which is the responsible body in Turkey to make measurements of solar irradiation. The comparisons are based on monthly mean daily values of global and diffuse solar irradiation and are carried out by statistical errors: mean bias error and root mean square error. The results showed that the methodology developed by the authors has shown better performances in estimating the monthly mean daily global and diffuse solar irradiation amount for Turkey.     

An investigation of double-glass-covered trapezoidal salt-gradient solar pond coupled with reflector

In the present study, a trapezoidal salt-gradient solar pond (TSGSP) has been investigated experimentally. The top surface of solar pond has been covered with double-glass cover in order to reduce the evaporative and convective losses from the top. This results in increase of temperature even in the top zone of the solar pond and leads to more volume utilization for heat storage in the pond. A reflector made of aluminium sheet has been used to enhance the solar intensity on the solar pond during sunny hours. A procedure, to determine optimum tilt angle of reflector in order to utilize maximum amount of solar energy at noon, has been proposed. The use of reflector enhanced the average solar intensity on the top surface of solar pond by 22%. The maximum average temperature of trapezoidal solar pond with glass cover and reflector has been observed to be 70.5°C. The thermal efficiencies of LCZ, NCZ and UCZ for the trapezoidal solar pond with double-glass cover and reflector have been estimated to be 32.73%, 23.22% and 5.30%, respectively. In addition to experimental investigation, the sunny area ratio of TSGSP has been theoretically computed and compared with the cuboid solar pond having same top surface area and depth in order to see the effect of pond shape on sunny area ratio. The average yearly sunny area ratio of trapezoidal solar pond has been determined to be 11% higher than that of cuboid one.     

厌氧发酵产沼气过程中脱氢酶活性检测工艺及其优化

为了优化脱氢酶活性这一指标在厌氧发酵产沼气系统中的检测方法,分别以小麦秸秆、羊粪及其混合原料(质量比1∶1)为发酵底物,通过Box-Behnken试验及响应面分析法确定并优化了沼气发酵系统中碘硝基四唑紫法脱氢酶活性的检测工艺,并对脱氢酶活性与甲烷产量进行了相关性分析.结果表明,3种底物均以乙醇作为萃取剂,以甲醛作为终止剂时显色效果最好.分别以秸秆、粪便及其混合为发酵底物时,脱氢酶检测在pH值分别为6.5、7.2、7.7,反应温度均在37℃下,碘硝基四唑紫质量分数均为0.15%,反应时间均为50 min时比色效果最好.相关性分析显示,厌氧发酵产沼气系统中脱氢酶活性与甲烷产量相关性显著.     

太阳跟踪反射聚光户外加速试验研究

太阳辐射是引起有机材料老化的最主要原因.由于拉萨高原地区的太阳辐射年总量比内地同纬度高出约1倍,在拉萨进行有机涂层样品的户外暴露试验,其老化速度可大大提高.通过在拉萨试验站对4种常用的有机防护涂层开展太阳跟踪反射聚光户外加速试验和自然暴露试验对比研究,优选出了环境适应性好的材料,并验证了其加速性.     

云对太阳紫外辐射的影响

云对到达地面的太阳紫外辐射有着重要的影响,根据在香河综合观测站１年的观测资料,利用相关分析,得到了计算云天条件下太阳紫外总辐射的一种经验公式,计算结果比较令人满意。对阴天太阳紫外总辐射的减弱作了简单的分析。     

固定化脱色菌－活性污泥的脱色性能研究

将所筛选的高效脱色菌群,采用聚集－交联法固定在活性污泥上,形民絮状立体网状微观结构。固定化脱色菌－活性污泥的脱色酶活力较未经固定的活性污泥提高７０％左右。经厌氧条件下处理针织厂印染废水,色度平均去降率为７７．３％,ＣＯＤＣｒ平均去除率为６５．１％。     

固定化微生物对水胺硫磷降解活性评价指标的研究

对水胺硫磷水样在生物降解前后的性能评价指标进行了研究,结果表明,有机磷,农药含量及降解率与ＣＯＤＣＲ及其去除率分别呈高度正相关,因此,选用ＣＯＤＣＲ去除率作为固定化微生物对农药降解活性的常用评价指标是适宜的。文中还给出由试验数据的回归方程及其显著检验结果。     

Organic residue decomposition: The minicontainer-system a multifunctional tool in decomposition studies

The Minicontainer-test, first described by Eisenbeis (1993), was designed to study the kinetics of organic residue decomposition at a microsite level. It is derived from the litterbag technique and consists of polyethylene minicontainers (volume about 1.5 cm³) filled with a test substrate (litter, straw, cellulose, etc.). The minicontainers (MCs) are closed at either end with plastic gauze discs of variable mesh size (e.g. 20 μm, 250 μm, 500 μm or 2 mm). A definite number of such units are inserted into PVC-bars, which can be implanted into the soil horizontally or vertically, or be exposed on the soil surface horizontally. The bars are very stable and can be exposed in different environments for months to years. If required, the bars can be removed temporarily and stored, e.g. during soil cultivation. Should fresh litter be used, two phases of decomposition can be distinguished: a fast initial phase, which can be mainly related to the effect of leaching, and a second slow phase depending mainly on the activity of soil organisms and litter quality. Several questions can be addressed to investigations using MCs, e.g. 1) parts of the soil fauna which are involved in decomposition (nematodes, microarthropods, and smaller specimens of the macrofauna, e.g. enchytraeidae, diplopods and dipteran larvae) can be extracted from the litter substrate using a miniscale high gradient extractor, 2) the organic mass loss of litter can be determined, 3) microbial biomass (C_mic, N_mic) can be assessed by fumigation extraction and 4) microbial activity (respiration) in the test substrate can also be assessed by use of standardised methods. Compared to litterbag studies, the larger number of small replicate units improves the statistical evaluation. Until today the Minicontainer-test has been applied in forestry and agriculture, e.g. studying the effects of liming, soil restoration and the application of insecticides, e.g. Diflubenzuron (Dimilin) and Btk (Bacillus thuringiensis var.kurstaki).     

施工现场的风险管理应用研究

风险管理理论已广泛应用于项目的设计、采购及施工等各个阶段。在建设项目施工阶段的应用,特别是在施工事故的主动预防领域的应用,国外企业已取得不少成效。通常建设项目的施工现场由一系列的土建、安装、试验等施工活动组成,每一项施工活动又分解为不同的施工步骤,各施工步骤之间又存在多种工艺关系或组织关系,结合这些关系的特点,如果能对每一步骤中存在的危害进行识别、评价并根据评价结果采取相应的控制措施,则整项施工活动的风险可以从"源"上消除或降低到可接受程度,从而实现安全。针对施工现场施工活动多样、人员流动性大等特点,通过对施工现场的风险管理的应用研究,以期为各级从事现场的管理技术人员提供一种便于现场进行施工风险控制的实践方法。